Method for atomizing by supersonic sound vibrations



Dec. 5, 1950 1'. o. JdEcK 2,

unmon FOR ATOIIZING BY SUPERSONIC sounn vxamnons 1 Filed Jan. 29, 1946 2Sheets-Sheet 1 V6 INVENTOR. 75 01/45. 7656" Patented Dec. 5, 1950 UNITEDSTATES PATENT OFFICE METHOD FOR ATOMIZING BY SUPERSONIC SOUND VIBRATIONS4 Claims.

This invention relates to supersonic generators for changing liquidsinto vapors or small droplets and to a method for effecting such change.

One object of this invention is the changing of liquids into vapors orsmall droplets and the homogeneous mixing of vapors or gases and themethods for the accomplishment thereof, with particular application ofsuch methods to the more eflicient operation of internal combustion,turbine or other similar prime movers as well as those operating from asource of substantially constant pressure, by subjecting them to highfrequency sound vibrations caused by the escape of gas or air underpressure through an orifice and amplified by the discharge column offluid tuned to resonate with the high frequency sound vibrations soproduced, thereby subjecting fluids so introduced into a chamber or thelike to greater disruptive forces so as to break them up into finelydivided and well distributed droplets.

Another object of this invention is to subject one or more liquids tosupersonic waves to cause them to break up into finely divided dropletsand tomix thoroughly and uniformly.

Other objects of this invention are to distribute evenly particlessuspended in a gas or gases, to distribute evenly particles such aspigments in one or more liquids and blend the same, to break up and.thoroughly mix and blend several diflerent kinds of liquids and/or gasesto produce a homogeneous mixture containing each liquid or gas or bothin a predetermined proportion and to subject streams of vaporized fluidto great disruptive forces so as to break up the same into more finelydivided and more equally distributed droplets.

Another object of this invention is the provision of asupersoniccarburetor.

Another object of this invention is to provide a fuel-burning jet ornozzle and the application of such to gas turbines and steam or othervapor pressure generators.

Other objects of this invention will appear as the description proceedsin connection with the drawings illustrating several embodiments, and inwhich,

Figure 1 shows an embodiment of means for breaking up liquids bysupersonic effects;

Figure 2 shows another embodiment utilizing a type of nozzle used inperfume atomizers or paint spray guns but with vacuum and wave poweramplifierv added;

Figure 2a shows the embodiment in Figure 2 provided with pressure (orvacuum) equalizing valves;

Figure 3 shows the invention carried out in connection with another typeof spray nozzle used in paint spray guns;

Figure 4 shows another means for increasing the vacuum and consequentlythe break up" produced with the type of nozzle shown in Figure 2;

Figure 5 shows a. combination of the spray nozzle of Figure 2 with anadjustable cavity member of the type shown in Figure 1;

Figure 6 shows an embodiment for drawing different liquids from aplurality of separate containers into a resonance chamber and blowingout a homogeneous mixture of varying predetermined proportions;

Figure 6a shows the embodiment in Figure 6 provided with pressure (orvacuum) equalizing valves;

Figure 7 shows a device for producing a more complete break up oftheparticles of liquid atomized; and

Figure 8 shows a carburetor employing the principles of my invention,more particularly the embodiment shown in Figure 6a.

A jet of gas issuing from an orifice is not constant but is definitelyintermittent in character. To a certain extent this is true of liquidescaping through an orifice under high pressure. Small somewhatconically shaped pufis emerge, producing a pulsating stream ofalternately compressed and rarified gas which is roughly similar to astream of bullets from a modern machine gun.

In Figure 1 there is disclosed one embodiment of a supersonic generatorcomprising an air tube [0 provided with a conical orifice and a cavitymember I] provided with a conical end. By adjusting the distance betweenthe efflux end of the air tube and the cavity member, as well ascoordinating the diameter of the air jet and that of the cavity togetherwith its depth in the cavity member, vibrations can be efficientlygenerated and propagated in considerable strength in a direction atright angles to the axis of the air jet. The axes of the jet and cavitycoincide. The jet and cavity are usually circular in cross section.

In order to increase the intensity or eificiency of the supersonicgenerator, a chamber is provided around the air tube by means of acylindrical member l3 here shown as the end of a liquid supply pipe l4.Any suitable provision, such as a threaded connection (not shown) may bemade for adjusting the air tube 10 in the liquid supply pipe I4. Thewalls of the chamber surrounding the end of the air tube produce a smallcircular orifice allowing liquid to enter the cylindrical chamber at itsouter diameter and parallel to its axis in the form of a cylindricalshell, the diameter of which is so calculated as to be in resonance withthe supersonic vibrations set up by the generator which comprises theair tube and the cavity member. This increases the break up of theliquid considerably.

The device shown in Figure 1, when used as a carburetor, is found highlysatisfactory. An engine equipped with this device produces more powerand runs well on many different kinds of fuel such as alcohol andvarious mixtures of kerosene, fuel, crude and the light oils, andgasoline; no choking is necessary, and starting is easier. While theillustration is more or less diagrammatic, its connection with theintake manifold is obvious by reference to Figure 8.

In Figure 1" the two elements In and II alone without the supply pipe 14and the cylindrical member I3 constitute the well-known Hartmannsupersonic generator. When this simple device is placed in the intakemanifold of a conventional gasoline engine, a better break up of theliquid particles occurs which is desired for better fuel economy andimproved engine performance. I

In Figure 2 is shown a device embodying the usual type of nozzle used inperfume atomizers, some types of spray guns and similar apparatus andwhich comprises an air tube l6 which is preferably threaded or otherwiseadjustably secured in a liquid spray tube I! provided with a cylindricalend section l8 surrounding the end of the air tube l6. When the distancebetween the end of the air tube and the end of the cylindrical endsection I8 is properly adjusted, a maximum vacuum will be obtained inthe liquid chamber provided by the cylindrical end section. The deviceincludes a tube 20 which closely fits over the discharge nozzle, andwhich produces a much higher vacuum in the liquid chamber and a muchbetter break up of the liquid.

The use of this tube produces a loading effect such as is performed by amegaphone as well as the tendency to compound the jet. This tube must beof the proper length as too short a tube will have no practical effect,and too long a tube will interfere with the efllux. It is found that bythe use of the proper length of tube 20 the supersonic vibrationsgenerated by the nozzle are resonated to such an extent that the vacuumand, therefore, the eficiency of the device is greatly increased.

In Figure 2a a pipe I'I' provided with a valve V1 is connected to thetube 20 and to the pipe I! by a connection provided with a valve V2. Thevalves here perform the function of either equalizing the pressures (orvacuum) by tying together the front and rear of the jet or mixing fluidsor gases with each other before being subjected to full supersonic forceat the point of issue of the jet.

Figure 3 shows another type of spray nozzle used in paint spray guns andis structurally somewhat the same as that disclosed in Figure 2. and isalso in principle substantially the same except that the air pressure isapplied where the liquid entered, and the liquid enters where the airwas applied in Figure 2.

This device comprises a liquid spray tube 22 which may be threaded intothe closed end of a cylindrical member 23 on the end of an air supplytube 24, providing an air pressure chamber. The open end of thecylindrical member or air chamher is provided with an inner conicalface25 to direct the air over the edge of the end of the liquid supply tube22. It is found that supersonic vibrations exist in the air pressurechamber 23 as well as in the air jet. If a glass tube be placed asindicated by the dotted lines and partially filled with light cork dustor lycopodium, the characteristic dust figures appear, indicating thatvibrations are set up behind the air orifice as well as in front of it.This is true of all other types of jets shown herein. In this device aplate 21 provided with a conical hole 28 having sharp edges as indicatedis placed at the proper distance away from the face of the nozzle toproduce resonance. Air passing over the sharp edges of the conicalopening 23 further accentuates the vibration condition in the air streamwhich is desired for better break up.

Figure 4 discloses the type of nozzle shown in Figure 2, and by placinga flat plate 30 in front of it as shown, the vacuum on the liquid in thecylindrical chamber I8 is increased and consequently the break up" ofthe liquid is increased at the point where the mixture escapes past theopening formed by the edge of the wall of the cylindricalchamber i8 andthe flat plate In Figure 5 is shown the combination of the nozzleconstruction shown in Figure 2 with a modified form of the cavity memberll shown in Figure 1.

The cavity member comprises an outer-supporting member 32 which issomewhat equivalent to the member 30 in Figure 4, a sleeve member 33provided with a conical end 34, and which may be adjustable in themember 32, and a rod 35, which may be adjustable in the sleeve member 33by means of which the position and depth of the cavity 36 may beadjusted. In this embodiment the distances between the end of the airtube and the end of the chamber 13, the distance between the end of thechamber 18, and

.the end face of the member 32, and the length and position of thecavity can be so adjusted in resonance as to obtain a very high degreeof break up" and efliciency.

The nozzle designs which discharge in a plane perpendicular to the axisof the et of air may be used in spraying and dusting devices. The deviceshown in Figure 2 throws a well broken up stream coincident with theaxis of the jet and is directly adapted for use as a carburetor orindividual fuel injector.

In Figure 6 isdisclosed a device which is highly efficient in breakingup a liquid and in discharging the same as a stream coincident with theaxis of the jet. This device includes as in Figure 3 a liquid pipe 22adjustable in the closed end of the cylindrical chamber 23 on the end ofthe'air pipe 24. Surrounding the cylindrical chamber 23 is a cylindricalmember 40 providing a chamber into which liquids may enter throughliquid supply pipes 4| and I2 which may be equipped with controllingvalves, as shown in Figure do, by means of which the amounts of theseveral liquids that may be drawn into the chamber in the cylindricalmember 40 may be controlled.

Mounted in the open end of the'cylindrical member 40 is a disc-likenozzle 46 which is adjustable toward and away from the end of thecylindrical member 23 and by selecting the proper radius for thecylindrical member 40 and adjusting the distance between the nozzlemember 46 and the end of the cylindrical member 23, the liquid in thechamber 40 may be caused to be in resonance with the vibrations producedat the nozzle comprising the end of the tube 22 and the end of thecylindrical member 23 which is about equal to the diameter of the tube22. The nozzle disc 46 is provided with an outwardly tapering port 41the angle of which isdetermined by the natural pattern of efllux fromthe nozzle zip azszformed by the shapes of tube 22 and mem- This typemakes it possible to draw by its own vacuum a plurality of differentliquids from as many separate containers into the resonance chamber andblow out a homogeneous mixture of varying proportions of each. which maybe controll-ed at will by control valves as described in connection withFigure 6a, in the pipes leading from various containers or sources ofsupply. The number of containers and pipes leading to the resonancechamber may be increased to a large extent. It has been found thatpowerful supersonic vibrations are set up throughout the system, and,therefore, that liquids introduced into the resonance chamber aresubjected to a terrific shaking-up.

In Figure 6a the pipe 22 is connected by branch pipes 22a and 22b to thepipes 4| and 42 and valves V2, V3, V4, V5 and V5 are provided in thepipes 22a, 22b, 24, 4| and 42 to perform the function of eitherequalizing the pressure (or vacuum) by tying together the front and rearof the jet or mixing liquids or gases with each other before beingsubjected to full supersonic force at the point of issue of the jet.

Figure '7 discloses a, device which produces a more complete break up.This device includes a liquid pipe 50 which projects into the taperedend of a duct member 5| and which is relatively adjustable with respectthereto. The member 5| includes a resonance chamber 52 and a flaringoutlet 53 of an angle determined as in the device in Figure 6 and whichis provided with radial openings 54 of increasing lengths toward itsouter end. The dimensions of the openings 54 in the direction of thelength of the outlet of the member 5! and radially thereof are adjustedor chosen to resonate with the vibrations in the chamber52. Thevibrations in an open pipe are reflected as a rarification at the ends,and, therefore, the rarifications are at the outer ends of the openings54. The best break up occurs at the point of rarification of the waveand, therefore, the best results may be obtained by means of an externaldraft of air flowing in the direction of the arrow which carries awaythe well broken up liquid at the point of rarification. The liquid canalso enter the jet through a pipe 56a.

All of the various jet designs as described in Figures 1, 2, 3, 4, 5, 6and 7 are eflicient fuel burners of fuel in both liquid and gaseousform.

The designs as shown in Figures 2, 2a, 6 and 6a are the most useful asfuel burners because of their discharge axis coinciding with the axis ofthe final efllux of the air-fuel mixture.

A vibrator or carburetor built in accordance with the principlesdisclosed in Figures 6 and 6a is shown in Figure 8 of the drawings.

The carburetor comprises a body portion 60 provided with a boreconstituting a compressed air chamber 6| into which air under pressureis supplied through a tube 62 controlled by an air valve 63. Mountedwithin and concentric with the wall of the chamber 6| is a liquid nozzle64 secured therein by a compressible packing '65 and tightening nut 66.The upper end Of the nozzle is provided with a needle valve 68cooperating with a restricted section 69 in the bore of the fuel nozzle64 and controlling the amount of fluid that may be admitted to thenozzle from a fuel inlet pipe 19 or 99.

The lower end of the chamber 6! is provided with a restricted outlet I2concentric to and axially aligned with the end of the fuel nozzle 64. Byadjusting the nozzle 64, the correct compressed air orifice at betweenthe end of the fuel nozzle and the restricted outlet 12 of the chamber6| for producing the desired supersonic vibrations may be determined.

The lower end of the body 60 is Provided with an enlarged resonancechamber 16, the walls 11 of which are threaded to receive a disc-likenozzle- 18 which may be locked inadjusted position by a lock nut 19. Foreach setting of the fuel nozzle '64 the disc nozzle 18 controlling thesize of the resonance chamber is adjusted for maximum vacuum in the fueldelivery line 10 and 10a as well as the line 99 when desired. Themixture of compressed air and finely divided fuel blown out through thedisc nozzle I8 enters an air mixing chamber '80 into which air is drawnin amounts controlled by a valve or gate 8|. From there the mixturepasses into the throttle tube 83 and past the throttle 84 into theintake manifold 85.

The wall ll of the resonance chamber 16 is provided with a peripheralradial port communicating by means of a pipe 9| controlled by a fuelselector valve 92 with the fuel line 10 and through an air bleed valve94 with the outside atmosphere, by means of which the mixture iscontrolled through mechanism such as the pantograph type movementcomprising the arm 96, link 91 and the upper extension of the valve BI.

The fuel pipe 10 may be equipped with a valve 92V,- and other pipes 98and 99 connected to other sources of liquids or gases may be controlledby valves 98V and 99V, and their common connection N10 with the pipe 10may be controlled by a valve I06V whereby any two or three liquids orgases may be injected in any desired relative volumetric proportionsinto the mixture. By this means it would be possible to add water vaporto the mixture in an easy and eflicient manner.

With the air bleed valve 94 and the needle valve 68 closed, and the fuelselector valves 92 and H34 closed, the fuel nozzle 64 is adjusted toproduce the proper supersonic vibrations, and then the disc nozzle 18 isadjusted to cause resonance of the air in the resonance chamber 16 withthe supersonic vibrations set up at the fuel nozzle 64 to producemaximum vacuum in the fuel line 10 and a second fuel line Illa. Theneedle valve 68 is then adjusted to control the admission of fuelthrough the fuel nozzle 64, and the bleed valve 94 is opened to controlthe mix: ture in the resonance chamber 16 b means of the mechanismconnected to flapper valve 8|. This is in turn actuated by a suitabletension spring I92 tending to keep opening I03 at a minimum. As thedemand for fuel by the engine is increased, valve 8| is moved inward tosome position as shown in Figure 8 and comes to rest at a point wherethe spring tension and the air pressures on both sides of valve 8|balance; as the demand decreases, valve 8| tends to close and at thesame time reduces the vacuum on the fuel lines as explained above,thereby keeping substantially a constant fuel air ratio fed to theengine.

Fuel valve 92V in the line 10 and the valve I04 in the line 10acontrolling the fuel flow lines to two separate tanks each containingdifferent fuels can be connected to and controlled by flapper valve illby a linkage similar to that shown by arm 96 and link 91 but connectedto the aforesaid fuel valves. Under these conditions it might bedesirable to eliminate the automatic control of the air bleed valve 94in which case it issimply disconnected from the linkage and closed oradjusted at a fixed position. In this manner the fixed fuel-air ratio isalso maintained by the demand of the engine.

One of the features of this carburetor is its ability to deliver fromseparate tanks a plurality of fuels to the engine after mixing them 5thoroughLv 'in a controlled proportion. This is done by apantograph orother means (not dis,- closed) connecting the proportioning valves inthe various fuel lines as is understood. If the gas cock .holes aresubstantially at right angles to 10 each other, it can be seen that amovement in either direction will open one and close the other. Anyintermediate position will produce a corresponding relative opening. Ifthis linkage were connected to a thermostat I01, actuated b the istemperature of the engine I08 through other\ links I06 and I09, then theproportion of liquid fuels entering the fuel air mixcould be socontrolled. Without the thermostatic feature, the liquid fuel ratio iscontrolled manually or by any 20 other desirable mechanical means.

It will be understood from the foregoing description that one of theimportant features of the invention resides in the use of a chamber,associated with a source of supersonic waves and with one or moresources of liquid, the said chamber being so constructed and arranged asto be resonant to the frequency of the supersonic waves. By thisconstruction and method, the supersonic vibrations within the resonancecham-- ber are greatly intensified and hence the degree of vaporizationof the liquid or liquids is materially increased.

It will be further understood that the design of the various parts ofthe devices herein disclosed follows well-known acoustical principlesapplicable to the resonance of sound waves. For example, such devicespreviously described embody various combinations ofresonant cavities ofthe closed and/0r open "organ pipe character. 4 More particularly andreferring to Fig. 6, the resonant cavity or chamber defined by member 40comprises three portions, namely the diameter of the member 40, thedistance between the nozzle member 46 and the end of the cylindricalmember 23, and the length of the member 46. The aforesaid diameterportion corresponds to a closed organ pipe in which event the diametershould be equal to an odd number of quarter wave lengths correspondingto thesupersonic fre 5o quency supplied. On the other hand, the distancebetween the members 46 and 23 and the length of the member 46corresponds to the open "organ pipes. Thus in accordance with the lawsgoverning resonance of such open pipes, these lengths should be equal to'an even number of quarter wave lengths'corresponding to the supplyfrequency. In this manner, the chamber defined by the member 40 will beresonant to the frequency of the supersonic vibrations supplied theretoand will be greatly intensified in order to secure a high degree ofbreaking-up" of the liquid or liquids.

The description of the invention with reference to preferred embodimentsillustrated for purposes of disclosure is not to be considered limiting, and it accordingly is to be understood that applicant reserves theright to all such changes and modifications as fall within theprinciples of this invention and the scope of the appended 79 claims.

I claim:

1. The method of intimately mixing liquids which comprises dischargingconcentric streams of said liquids under pressure into a soundaugmenting resonance chamber, and subjecting said liquids to a jet ofsupersonic sound vibrations in said chamber, whereby the liquids arehomogeneously and intimately mixed, said chamber being resonant to thefrequency of said supersonic sound vibrations.

2. The method of breaking up a liquid into finely divided particles tovaporize the same, which comprises continuously supplying underpressure, into a chamber at one end thereof, a

jet of supersonic sound vibrations, said chamber being resonant to thefrequency of said vibrations to thereby intensify the vibrations,continuously supplying a stream of liquid to said chamber to subject theliquid to the intensified supersonic vibrations in the chamber toproduce a vaporized mixture, and discharging the vaporized mixture fromsaid chamber at the other end thereof.

3. The method of breaking up a liquid into finely divided particles tovaporize the same, which comprises continuously supplying underpressure, into a chamber at one end thereof, a jet of supersonic soundvibrations, said chamber being resonant to the frequency of saidvibrations to thereby intensify the vibrations, continuously supplying astream of liquid to said chamber concentrically of said jet to subjectthe liquid to the intensified supersonic vibrations in the chamber toproduce a vaporized mixture, and discharging the vaporized mixture fromsaid chamber at the other end thereof.

4. The method of breaking up a liquid into finely divided particles tovaporize the same, which comprises continuously supplying underpressure, into a chamber at one end thereof, a jet of supersonic soundvibrations, said chamber being resonant to the frequency of saidvibrations to thereby intensify the vibrations, continuously supplying astream of liquid to said chamber concentrically of said jet, supplying aseparate stream of liquid to said chamber, the

liquids in said chamber being subjected to the intensified supersonicvibrations therein to produce a vaporized mixture, and discharging thevaporized mixture from said chamber at the other end thereof.

THOMAS D. JOECK.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 371,157 Wright Oct. 4, 188'!692,798 Seltzer Feb. 4, 1902 1,107,244 Carter Aug. 11, 1914 1,197,600Brown Sept. 16, 1916 1,253,522 Patterson Jan. 15, 1918 1,919,164 JeromeJuly 18, 1933 1,939,302 Heaney Dec. 12, 1933 2,149.115 De Foe et al.Feb. 28, 1939 2,238,806 Doubledent Apr. 15, 1941 2,244,467 Lysholm June3, 1941 2,324,147 Gendron July 13, 1943 2,364,987 Lee Dec. 12, 19442,391,422 Jackson Dec. 25, 1945 2,411,181 Altorfer Nov. 19, 1946 OTHERREFERENCES Soundless Sound Waves," vol. 162, #3, pp. 148-149 01 Mar.1940.

